If you want more control... or to actually compose 8-bit music I recomend Famitracker http://www.youtube.com/watch?v=Ep3g_zXfna4
Submitted by Petey on Fri, 06/24/2011 - 19:58
Here is a free application that is available for Linux, Windows, and OSX that will allow you to create a wide range of 8 and 16 bit sound fx for your game.
Windows/Linux: http://goo.gl/tpkaa
OSX: http://thirdcog.eu/apps/cfxr
To be fair, I do not use this to compose music, but to make simple sounds for retro games. I was using it the other da for a project, and thought I would share it.
I will check out your link though as I am always looking for more free software that is useful.